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791.
792.
To evaluate whether differences in demographic or behavioural factors might explain differences in reported or diagnosed sexually transmitted infections (STI), we have compared data from 1097 Tanzanian and Norwegian STI patients. Most demographic data were similar, whereas some behavioural data differed. Norwegian patients reported significantly higher numbers of sexual partners than Tanzanian. Thirty-three percent of Tanzanian patients tested positive for HIV antibodies, females more often (43%) than males (26%). Approximately one-third and two-thirds of the female HIV-positive Tanzanian STI patients had already seroconverted at the age of 25 and 30 years, respectively. The national differences encountered probably reflect cultural differences, different panoramas of STI and a lower accessibility to optimal health services in Tanzania. Lack of expected statistical associations between some of the data in the Tanzanian STI group might question the validity of the retrospectively collected data in this group, or indicate that questions not included in the questionnaire might be of importance.  相似文献   
793.
Introduction Shorter adult stature has been attributed to early sexual maturation, as well as early adiposity, but it is not clear if these factors are interrelated.Results and discussion A number of 1,605 Norwegian adolescents were followed from early (baseline) to late adolescence (follow-up). Maturational timing was assessed by self-reports of pubertal status (pubertal development scale, PDS) in boys and age at menarche (AAM) in girls. Height, weight and waist circumference were measured at baseline and at follow-up. Differences in height at follow-up and height gain related to the timing of sexual maturation and the level of central adiposity (i.e. high or low waist circumference) at baseline were estimated using general linear modelling. At follow-up, the median height was 180 cm in boys and 167 cm in girls. Early maturing boys and girls with relatively high central adiposity at baseline were, on average, 5.7 cm (P value<0.001) and 3.6 cm (P value<0.001) taller than early maturing boys and girls with low central adiposity. Differences in stature related to central adiposity were less pronounced for intermediate and late maturing boys and girls. The height was lowest in boys (176.6 cm) and girls (163.8 cm) who had matured early and had low central adiposity at baseline. Height gain during follow-up was independent of the level of central adiposity, but was closely related to the timing of sexual maturation. The association between the early timing of sexual maturation and subsequent height was modified by the level of central adiposity in early adolescence.Conclusion The results suggest that early maturity combined with adiposity yields higher stature than early maturity and leanness.  相似文献   
794.
The authors investigated a possible association of supplemental folic acid and multivitamin use with placental abruption by using data on 280,127 singleton deliveries recorded in 1999-2004 in the population-based Medical Birth Registry of Norway. Odds ratios, adjusted for maternal age, marital status, parity, smoking, pregestational diabetes, and chronic hypertension, were estimated with generalized estimating equations for logistic regression models. Use of folic acid and/or multivitamin supplements before or any time during pregnancy was reported for 36.4% of the abruptions (0.38% of deliveries) and 44.4% of the nonabruptions. Compared with no use, any supplement use was associated with a 26% risk reduction of placental abruption (adjusted odds ratio = 0.74, 95% confidence interval: 0.65, 0.84). Women who had taken folic acid alone had an adjusted odds ratio of 0.81 (95% confidence interval: 0.68, 0.98) for abruption, whereas multivitamin users had an adjusted odds ratio of 0.72 (95% confidence interval: 0.57, 0.91), relative to supplement nonusers. The strongest risk reduction was found for those who had taken both folic acid and multivitamin supplements (adjusted odds ratio = 0.68, 95% confidence interval: 0.56, 0.83). These data suggest that folic acid and other vitamin supplementation during pregnancy may be associated with reduced risk of placental abruption.  相似文献   
795.
796.
Soluble mesothelin-related protein (SMRP) in serum is potentially a sensitive marker of malignant mesothelioma (MM) diagnosis and progression, and may be useful as screening marker. Mesothelin expression in tumors is regarded as a sensitive marker for diagnosis and disease progression, and is a candidate prognostic marker. Levels of SMRP, CA125 and CYFRA 21-1 in pre-diagnostic (1-30 years) serum samples from 47 mesothelioma cases and 141 matched controls were analysed. Mesothelin expression in tumors was assessed. The association between biomarker level and mesothelioma risk and survival was analysed, adjusting for asbestos exposure. Survival related to tumor mesothelin expression, age, sex, histological type, location, asbestos exposure and pre-clinical SMRP was analysed. There was no significant association between biomarker levels and mesothelioma risk when analysed as continuous variables or as tertiles. Biomarker levels <10, 10-19 and >or=20 years before diagnosis were not significantly associated to mesothelioma risk. Mesothelin expressed in >50% of tumor cells was seen in 36 of 47 (77%) tumors. Mesothelin expression in <50% of tumor cells was a significant negative prognostic marker in all cases of malignant mesothelioma (median survival=6 months vs. 12 months, hazard ratio (HR)=2.49, 95%CI 1.17-5.27), and also when only epithelial mesothelioma was analysed (median=6 months vs. 14 months, HR=2.36, 95%CI 1.07-5.22). When adjusted for age and gender, the prognosis was still dismal, but non-significant (HR=1.85, 95%CI 0.85-4.05). High age (>65 years) was an independent negative prognostic factor that was related to both mesothelin expression and asbestos exposure. Mesothelioma of the epithelial type of the peritoneum had a significantly longer survival than epithelial type in pleura and was also related to mesothelin expression.  相似文献   
797.
Perianal fistulas: use of MR imaging for diagnosis   总被引:3,自引:0,他引:3  
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798.
OBJECTIVES: Few studies have investigated the impact of home safety promotion programmes on different social strata. The aim of this study was to investigate the distribution of effects of a community-based home safety programme on home injury rates among families with different connections to the labour market. METHODS: A quasi-experimental design was used, with pre- and post-implementation registrations covering the total populations below 65 years of age in the programme implementation area (population 41,000) and in a neighbouring comparison municipality (population 26,000) in Osterg?tland County, Sweden. RESULTS: In the intervention and comparison areas, households in which the adults were not vocationally active displayed the highest rates of home injury. After 6 years of programme activity, the home injury rates for males and females in all social status categories displayed a decreasing trend in the intervention area. The opposite was true for the comparison area, i.e. the incidence of injury increased, with the exception of females in non-vocationally active households. The decline in injury rates in the intervention area was statistically significant for males and females in the employed category and for males in the non-vocationally active category. Changes in injury rates in the comparison area were not statistically significant. CONCLUSION: The programme was partially successful in that it reduced the injury rate in non-vocationally active households, but it did not influence the injury rate in the employed households. The study design did not allow for conclusions regarding why the post-intervention injury rates remained higher in non-vocationally active households. Further research on the association between the incidence of home injury and socio-economic factors is warranted.  相似文献   
799.
OBJECTIVES: To explore the association between drinking patterns, irrespective of whether alcohol was consumed in the event of the injury or not, and different injury variables; and to identify settings and situations in which risky drinkers have an increased likelihood of injury. STUDY DESIGN: The study population consisted of all patients aged 18-70 years registered for an injury according to ICD-10 at a Swedish emergency department during an 18-month period. After informed consent, the injury patients were screened for drinking habits by the AUDIT-C questionnaire. The gender, age and drinking pattern of injury patients were compared with the general population. METHODS: A total of 2782 patients aged 18-70 years were registered for an injury during the study period. The number of drop-outs was 631. Drop-outs include those who did not consent to participate, were severely injured, too intoxicated or did not fill out the questionnaire satisfactory. Thus, 77.3% of the target group were included for further analysis (1944 drinkers and 207 abstainers). The patients were categorized into three drinking categories: abstainers, non-risky and risky drinkers. Risky drinkers were defined according to usual weekly consumption of 80g or more of alcohol for women and 110g or more for men and/or heavy episodic drinking (i.e. having six glasses or more one glass=12g alcohol), or both, on one occasion at least once a month, valid for both women and men. To estimate the relationship between drinking patterns and the injury variables (environment, cause of injury, activity and diagnosis), odds ratios (OR) were calculated by logistic regression. Multiple logistic regression was used in order to control for age and sex differences between the various drinking and injury categories. RESULTS: The proportion of risky drinkers was higher in the study population compared with the general population in the same area. When controlling for age and sex, risky drinkers (OR 6.4(adj) Confidence interval CI 1.9-21.2) and non-risky drinkers (OR .4.5(adj) CI 1.4-14.5) displayed an increased risk for injury compared with abstainers, in amusement locations, parks, by or on lakes or seas, especially while engaged in play, hobby or other leisure activities (risky drinkers: OR 2.8(adj) CI 1.3-5.6; non-risky drinkers: OR 2.4(adj) CI 1.2-4.6). All differences between drinking patterns in external cause of injury disappeared when age and sex were considered. During rest, meals and attending to personal hygiene, the non-risky drinkers had a lower probability of injury compared with abstainers (OR 0.3(adj) CI 0.1-0.8). Non-risky drinkers had a higher probability than abstainers of suffering luxation (dislocation) or distortion (OR 1.6(adj) CI 1.1-2.5). Nine per cent of the study population reported that they believed that their injury was related to intake of alcohol. Half of this group were non-risky drinkers (CI for the 13.7% difference was 9.7-17.6). CONCLUSIONS: Few significant associations between drinking pattern and injury remained when age and sex were controlled for.  相似文献   
800.
Carbon monoxide (CO) is a dangerous poison in high concentrations, but the long-term effects of low doses of CO, as in the gaseous component of tobacco smoke, are not well known. The aims of our study were to evaluate the long-term effects of inhaled CO on the respiratory and cardiovascular system at doses corresponding to tobacco smoking and its effect on tumourigenesis and pulmonary neuroendocrine (NE) cells. Female Wistar rats were exposed to either CO (200 ppm) for 20 h/day (n=51) or air (n=26) for 72 weeks. Carboxyhaemoglobin was 14.7+/-0.3% in CO exposed animals and 0.3+/-0.1% in controls. In the lungs, no signs of pathology similar to that associated with cigarette smoking were observed, and no differences in number of pulmonary NE cells were observed between the groups. Chronic CO inhalation induced a 20% weight increase of the right ventricle (p=0.001) and a 14% weight increase of the left ventricle and interventricular septum (p<0.001). Histological examination of the myocardium did not reveal any signs of scarring. In the aorta and femoral artery, no signs of atherosclerosis were observed in CO exposed rats. No exposure related carcinogenic effects were observed. Spontaneous tumours were identified in 29% of CO exposed animals and in 28% of the controls. Our results suggest that low dose CO exposure is probably not responsible for the respiratory pathology associated with tobacco smoking. The effects on the cardiovascular system seem to involve myocardial hypertrophy, but not atherogenesis.  相似文献   
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